Latch bolt hold-back in lock



Jan. 7,1969 F. J. RUSSELL ETAL 3,420,561

LATCH BOLT HOLD-BACK IN LOCK Sheet of 2 Filed Sept. 20, 1966 M 54 mag gm W52 mafi .1- J 4 DM 5 n For B 3 3 ATTOQAIE YS Jan. 7, 1969 F. J. RUSSELL ETAL 3,420,561

LATCH BOLT HOLD-BACK IN LOCK Filed Sept. 20, 1966 Sheet 2 of 2 5% Fig/ 39 INVEN'IORS 151250 J RUSSELL z/cmoap 1,. new STIPQMG Y F250 L. Jenn/5 wgwlw United States Patent Ofiice 3,420,561 Patented Jan. 7, 1969 3,420,561 LATCH BOLT HOLD-BACK IN LOCK .Fred J. Russell, 8635 Otis St., South Gate, Calif. 90280,

Claims ABSTRACT OF THE DISCLOSURE The disclosure involves addition of a hold-back arm pivotally mounted upon a somewhat composite cam, the primary purpose of the cam being to extend and withdraw a dead bolt. There is an intermittently acting camming engagement between the hold-back arm and the cam such thatthe hold-back arm is normally held in an elevated position out of engagement with mechanism which shifts back and forth with movement of the latch bolt. In order to hold the latch bolt in withdrawn position, which is the aim of the mechanism disclosed, the latch bolt is temporarily held in withdrawn position and, while it is in Withdrawn position, the dead bolt actuating cam is manipulated in a direction first extending the dead bolt outwardly, during which motion the hold-back arm is shifted out of a raised position, which shifting is followed by a slight dropping of the position of the hold-back arm when the dead bolt actuating cam is withdrawn, so that in the dropped position, the hold-back arm will engage mechanism for holding the latch bolt temporarily in a withdrawn position.

The invention has reference to structure involving the releasably holding latch bolt in a retracted position. Although the invention is applicable to door locks generally, it is especially suited to door locks of the mortise type.

As locks of the kind herein made reference to are ordinarily used, it is frequently desirable to be able to set the latch bolt in a retracted or withdrawn position, making it unnecessary on such occasions to manipulate the knob or other handhold to open the door. There have been locks which have a latch bolt hold-back provision incorporated therein, but they generally have been somewhat complicated, requiring a relatively large number of extra parts over and above those used in locks where the latch bolt hold-back condition does not prevail.

On other occasions, locks have employed some extra device on the exterior which needs to be operated to set the latch bolt in retracted position.

It is among the objects of the invention to provide a new and improved lock incorporating a simplified structure, making it possible to releasably set the latch bolt so that it remains in retracted position.

Another object of the invention is to provide a new and improved lock structure, wherein the latch bolt can be set to remain in retracted position by mechanism which involves incorporating a very minimum number of extra parts into the device over and above those employed for lock functions which do not include the hold-back adjustment.

Still another object of the invention is to provide a new and improved lock structure, incorporating means for holding the latch bolt in retracted position which is operated by the dead bolt actuating mechanism, or a portion thereof, in such fashion that the adjustment can be quickly and easily made, and in such fashion that the manner of making the adjustment is relatively simple and easy to use.

Also included among the objects of the invention is to provide a new and improved lock structure, incorporating means for releasably holding the latch bolt in retracted position, wherein the construction and operation of the parts necessary for such adjustment incorporate proportioning and leverage arrangements, making the adjustment as one capable of easy operation and also one sutficiently rugged that it cannot be disturbed by misuse.

With these and other objects in view, the invention consists in the construction, arrangement, and combination of the various parts of the device, whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims, and illustrated in the accompanying drawings.

In the drawings:

FIGURE 1 is an end elevational view of a fragment of a door, showing the lock structure mounted thereon.

FIGURE 2 is a side elevational view of the lock structure, partially broken away and showing the latch bolt in extended position and dead bolt in withdrawn position.

FIGURE 3 is a longitudinal sectional view taken on the line 33 of FIGURE 2.

FIGURE 4 is a side elevational view, partially broken away, similar to FIGURE 2, but showing the relative position of parts, with both the latch bolt in retracted position and the dead bolt in withdrawn position.

FIGURE 5 is a fragmentary side elevational view of a portion of FIGURE 4, but showing the relationship of parts when the latch bolt is in withdrawn position and the dead bolt is in extended position.

FIGURE 6 is a still smaller fragmentary view, similar in general to FIGURES 4 and 5, showing the relationship of parts when the latch bolt is held in retracted position.

FIGURE 7 is a fragmentary cross-sectional view on the line 7-7 of FIGURE 6.

FIGURE 8 is a fragmentary longitudinal sectional view on the line 8-8 of FIGURE 6.

In an embodiment of the invention chosen for the purpose of illustration, there is shown a door lock, indicated generally by the reference character 10, mounted upon a door 11. For purposes of description, it may be assumed that the inside face of the door is at 12 and the outside face at 13. The door lock 10 is provided with a dead bolt 14 and a latch bolt 15 which extend outwardly through appropriate openings in an end plate 16 on an edge 17 of the door 11. The latch bolt 15 is adapted to be manipulated by both an outside knob 18 and an inside knob 19. A handle 20 manipulates the dead bolt 14. A key-actuated lock device 21 also provides for manipulation of the dead bolt 14. The parts defined up to this point are all mounted in a case 22 having the usual side walls and end walls or are operatively connected thereto and all are of substantially conventional construction for a lock of the type herein made reference to.

In the particular lock herein described by way of example, the latch bolt 15 is pivotally mounted at the location 23 and has a shaft 24 extending inwardly into the case 22, terminating in a flange 25, there being provided a spring 26, the function of which is to releasably hold the latch bolt 15 in the extended position of FIG- URE 2.

Normally, the latch bolt 15 is manipulated by one or another of the knobs 18 and 19. This is accomplished by rotation of a spindle 27 nonrotatably attached to the knobs 18 and 19. The spindle 27 rotates a rollback 28, either clockwise or counterclockwise, as the case may be, a clockwise rotation being shown in FIGURE 4. The rollback 28 moves against a block 29, moving it against the pressure of a compression spring 30, there being provided a lug 31 on the block 29 which moves against a latch bolt actuating lever 32. The lever 32 pivots about a point 33, and an upper end 34 is then moved against the flange 25 to withdraw the latch bolt 15. A spring keeper 35 engages the right-hand end of the spring 26, as shown in FIGURE 2, thereby causing the spring 26 to be compressed when the latch bolt 15 is retracted, the spring 26 therefore being the agency for extending the latch bolt 15 when the spindle 27 is released. A retracting lever link 36 is pivotally attached to the case 22 at the pivot point 37. Flanges 38 and 39 at the lower end of the lever link 36 overlie opposite sides of a flange 40 on the lever 32, so that as the lever 32 is forced in a clockwise direction, the lever link 36 is forced in a counterclockwise direction.

For manipulating the dead bolt 14, there is provided a spindle 41 which is rotated by means of the handle 20. A rotating cam or lever 42 is nonrotatably mounted upon the spindle 41 and is connected to the dead bolt 14 by means of a drive link 43. As the cam 42 is rotated in a counterclockwise direction, as viewed in FIGURE 2, the dead bolt 14 slides outwardly within a stationary section 48 to extended or locked position. =Upon rotation of the cam 42 in a clockwise direction, the drive link 43 is pulled inwardly, thus withdrawing the dead bolt 14 to which it is pivotally connected, by means not shown, to the position of FIGURE 2. When the dead bolt 14 is to be locked or unlocked from the outside by manipulation of the key-actuated lock device 21, an actuator 44, forming part of the key-actuated lock device 21, is rotated against one side or another of a recess 45, thereby to rotate the cam 42 either clockwise or counterclockwise, as the case may be. A yieldable detent 46, acting against a projection 47 on the cam 42, releasably holds the cam 42 in one position or another.

To hold the latch bolt 15 in withdrawn position, use is made of a hold-back arm 50. The hold-back arm 50 is pivotally mounted upon a pin 51 in a slot 52 in the cam 42. On the hold-back arm 50' is a hold-back shoulder 53 which faces inwardly, as shown in FIGURE 2. The hold-back arm 50 is also provided with a cam shoulder 54 adapted to engage a lower side of the slot 52, which may be designated as a cam shoulder 55.

In the flange 39 of the retracting lever link 36 is an opening 56 substantially in alignment with the hold-back arm 50. A lower edge of the opening 56 forms a holdback shoulder 57 which is adapted to cooperate with the hold-back shoulder 53 in the hold-back arm 50.

In operation, let it be assumed that the parts are initially in the position shown in FIGURE 2, the dead bolt 14 being withdrawn and the latch bolt 15 being extended by action of the spring 26. When the latch bolt 15 is withdrawn while the dead bolt 14 is in the position there shown, the hold-back shoulder 53 of the hold-back arm 50 will not be brought into engagement with the holdback shoulder 57 of the retracting lever link 36. This is because the hold-back shoulder 53 extends far enough toward the left, as viewed in FIGURE 2, so that, at the limit of motion counterclockwise of the retracting lever link 36, the wider portion of the hold-back arm 50 will continue to rest upon the hold-back shoulder 57. This position is shown in FIGURE 4. To engage the hold-back shoulders 53 and 57, the dead bolt 14 is extended by rotation of the spindle 41 and cam 42 in a counterclockwise direction, as viewed in FIGURES 4 and 5, for example. During this movement, the location of the center of the pin 51 is shifted slightly in a direction from right to left, as viewed in those figures. When the cam 42 is at the limit of its motion, as shown in FIGURE 5, the cam shoulder 54 of the hold-back arm 50 engages the cam shoulder 55 of the cam 42 and the hold-back arm 50 is held in an elevated position, as shown, with the smaller end extending through the opening 56. Thereafter, as the spindle 41 and cam 42 are rotated in a clockwise direction, as viewed in FIGURE 5, in response to rotation of the handle 20, the hold-back arm 50 will commence advancing to the broken line position of FIGURE and continue to advance until it occupies the solid line position shown 4 in FIGURE 6. In this position, the hold-back shoulder 53 of the hold back arm 50 will fall behind the hold-back shoulder 57 of the flange 39. This has the effect of holding the retracting lever link 36 at its innermost location, where the flange 39, bearing against the flange 40 on the lever 32, holds the lever 32 in its inward position. Accordingly, the shaft 24 and the latch bolt 15 attached thereto will be held in retracted position as long as the dead bolt 14 continues to be held in retracted position.

To release the latch bolt 15, it is necessary only to rotate the spindle 41 and cam 42 in a counterclockwise direction, as viewed in FIGURE 6. This operation extends the dead bolt 14 and at the same time lifts the hold-back arm 50 until the hold-back shoulder 53 thereon is lifted out of engagement with the hold-back shoulder 57, whereupon the retracting lever link 36 and lever 32 are released. This permits the lever 32 to rotate to the position of FIGURE 2 and allows the latch bolt 15 to extend. The latch bolt 15, of course, can be released in the manner just described, either by use of the handle 20 to extend the dead bolt 14 or by manipulation of the key-actuated lock device 21 acting through the actuator 44 upon the cam 42. 7

From the foregoing description, it will be apparent that the only part which needs to be added to other standard operating parts of a lock of this general descrip tion is the hold-back arm 50, all other parts being present in any event for the normal operation of the lock. The only operation necessary to set the latch bolt 15 in retracted position is to physically retract it by manipulation of one or another of the knobs 18 or 19 and then set it by first extending and then retracting the dead bolt 14. Release is automatic whenever the dead bolt 14 is extended.

In the embodiment shown, the dead bolt 14 and the drive link 43 have been shown. There are a number of lock functions which omit a dead bolt, but a latch bolt hold-back still would be desired. In such cases, the dead bolt 14 and the drive link 43 would be omitted, but the cam 42 or a cam similar thereto still would remain. Thus, the invention is applicable, whether or not the lock function includes a dead bolt. Also, some lock function might exclude one or the other of the handle 20 or the keyactuated lock device 21, but the result would be that the lock could only be operated from one side of the door to retain the latch bolt 15 in retracted position. Thus, the invention is applicable to every lock function which has a latch bolt.

While the invention has herein been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein, but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

Having described the invention, what is claimed as new in support of Letters Patent is:

1. In a lock, a case, a latch bolt assembly reciprocatably mounted in said case, a retracting link having one end movably mounted in said case and the other end in engagement with said latch bolt assembly, a rotating lever rotatably mounted in said case, a hold-back arm movably mounted on and carried by said rotating lever, and a hold-back shoulder on said hold-back arm, said retracting link having an opening therein in alignment with said hold-back arm and forming a hold-back shoulder engageable with the hold-back shoulder on the hold-back arm when the latch bolt assembly is in retracted position and said rotating lever is rotated, whereby to retain the latch bolt assembly in said retracted position.

2. A lock and latch bolt assembly therein, as in claim 1, wherein the hold-back arm is pivotally mounted on the rotating lever, said arm having a cam shoulder thereon in engagement with a complementary cam shoulder on said rotating lever when said rotating lever is rotated in one direction, whereby to move said hold-back shoulder of said hold-back arm away from engaging position with said hold-back shoulder on said retracting link.

3. A lock and latch bolt assembly therein, as in claim 2, wherein the distance between the pivotal mounting of the hold-back arm on the rotating lever and said holdback shoulder on the hold-back arm is less than the distance between said pivotal mounting of the hold-back arm on the rotating lever and the hold-back shoulder on said retracting link when the rotating lever is rotated in one direction, whereby to enable said hold-back shoulders to engage each other upon rotation of said rotating lever in the opposite direction.

4. A lock and latch bolt assembly therein, as in claim 2, wherein the hold-back arm extends substantially horizontally when said rotating lever has been rotated in one direction and when the cam shoulders are in engagement to enable said hold-back arm to be moved to a position wherein said hold-back shoulders are in engagement upon rotation of said rotating lever in the opposite direction.

6 5. A lock and latch bolt assembly therein, according to claim 1, including a spindle assembly in engagement with said latch bolt assembly, whereby said hold-back shoulders may be moved into engagement when the latch bolt is held in retracted position by said spindle assembly.

References Cited UNITED STATES PATENTS 1,168,725 l/1916 Hurd 70-135 2,454,920 11/1948 Heineman 70-150 3,141,320 7/1964 McConnell 292-165 X MARVIN A. CHAMPION, Primary Examiner.

J. R. MOSES, Assistant Examiner.

U.S. Cl. X.R. 70-150; 292-7 

